which old DSLR is that? even old DSLR can shoot fast action if you know how

anyway since u didnt mention what lens did she use, you're probably not really familiar with cameras so let us attempt to help u a bit

the main point of using a DSLR is the ability to change lenses. you can compare the cheapest, oldest DSLR and the newest, most expensive DSLR... it's very very hard to see the difference (unless it's under low light). lenses make or break the photos, not the DSLR.

to shoot fast action without blur, you need to get as much light as possible, in a short period of time, onto the sensor.

short period of time - so you'll 'freeze' the motion, i.e. wont get blurry photos. you can achieve this by setting the Shutter Speed. maybe 1/4000 should be quick enough. google or look through menus to learn how to set this in "shutter speed priority" mode.

the downside of using a fast shutter speed is you get less light in, i.e. darker photos. to balance this out, you need lenses that can allow a lot of light in by having a wider opening. look for lenses with an aperture of f/2.8 and below (smaller number = more light comes in). it can get expensive!

ideally for sports, get the nikkor 70-200 f/2.8 which is about rm7k. it's upwards of rm1.5k so that wouldn't be a problem now, wouldn't it?

i think u meant sony rx100. i googled sony n100 it's a media player lol

but then again a good lens + DSLR would beat rx100 any day

"sports mode" is just a 'shortcut' to a specific setting. you can do it on any DSLR.

trust me bro. she already has a DSLR, im 100% sure it's good enough for the job. just learn how. dont rely on whatever sports mode or what. learn about shutter speed n ISO n aperture n so on.

old DSLR + correct lens is way way way better than new DSLR + standard lens